Blades are used in a wide variety of fluid-accelerating and fluid-moving equipment, such as ventilation systems, blast fans, cooling fans, centrifugal blowers, impellers, propellers and the like. The fluid-accelerating and fluid-moving equipment typically includes a central rotatable hub and a plurality of radially-extending blades mounted onto the hub. Each blade may include a generally airfoil-shaped body having a low pressure surface and a high pressure surface located opposite the low pressure surface.
Due to the pressure forces, the fluid that flows over the high pressure surface of the blade typically remains attached to the blade. However, fluid that flows over the low pressure surface of the blade tends to separate from the blade, which creates a wake in the flow, primarily at the rear edge of the blade. The wake is a regime of chaotic air particles which can cause increased noise and a loss of efficiency. Accordingly, there is a need for a blade which has improved attachment of the flow thereto to improve the performance of the blade.